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A226883 Number of n-length words w over a 4-ary alphabet {a1,a2,...,a4} such that #(w,a1) >= #(w,a2) >= ... >= #(w,a4) >= 1, where #(w,x) counts the letters x in word w. 3

%I

%S 24,60,300,1260,6496,20916,95640,353760,1600104,5626764,23844002,

%T 88442445,387629456,1389902524,5788974504,21752247660,93252286444,

%U 340374221376,1409907258122,5335751835865,22620834658096,83728749708760,345377277971570,1315699675342065

%N Number of n-length words w over a 4-ary alphabet {a1,a2,...,a4} such that #(w,a1) >= #(w,a2) >= ... >= #(w,a4) >= 1, where #(w,x) counts the letters x in word w.

%H Alois P. Heinz, <a href="/A226883/b226883.txt">Table of n, a(n) for n = 4..1000</a>

%t Table[Sum[n!/Product[IntegerPartitions[n,{4}][[k,j]]!,{j,1,4}],{k,1,Length[ IntegerPartitions[n,{4}]]}],{n,4,20}] (* _Vaclav Kotesovec_, Jul 01 2013 *)

%Y Column k=4 of A226874.

%K nonn

%O 4,1

%A _Alois P. Heinz_, Jun 21 2013

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Last modified January 29 05:09 EST 2022. Contains 350672 sequences. (Running on oeis4.)